condition mean min max ZT0-3 1.83020085125 1.7089570840000001 1.9514446185 ZT4-7 2.3344766025 1.8781644595000002 2.7907887455 ZT8-11 3.3021408254999995 2.4892051625 4.1150764885 ZT12-15 4.88875502625 4.1430123725 5.63449768 ZT16-19 3.5238761545 3.4272847654999996 3.6204675435 ZT20-23 4.22428406675 4.129994762 4.318573371499999